Business Segments (Balance Sheets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Total assets	$ 668,021	$ 655,408	$ 770,520
Depreciation, depletion and amortization	19,276	23,680	28,070
Capital expenditures, excluding acquisitions of business	16,167	10,615	57,500
Operating Segments | NACoal
Segment Reporting Information [Line Items]
Total assets	287,011	303,138	389,964
Depreciation, depletion and amortization	12,682	17,067	22,003
Capital expenditures, excluding acquisitions of business	10,109	4,116	51,228
Operating Segments | HBB
Segment Reporting Information [Line Items]
Total assets	257,167	253,874	270,265
Depreciation, depletion and amortization	4,681	4,750	2,693
Capital expenditures, excluding acquisitions of business	4,814	4,365	4,516
Operating Segments | KC
Segment Reporting Information [Line Items]
Total assets	54,004	56,177	56,260
Depreciation, depletion and amortization	1,545	1,558	3,048
Capital expenditures, excluding acquisitions of business	1,188	1,806	1,193
NACCO and Other | NACCO and Other
Segment Reporting Information [Line Items]
Total assets	109,022	64,069	96,918
Depreciation, depletion and amortization	368	305	326
Capital expenditures, excluding acquisitions of business	56	328	563
Eliminations
Segment Reporting Information [Line Items]
Total assets	$ (39,183)	$ (21,850)	$ (42,887)